Stroke/thromboembolism and intracranial hemorrhage in a real-world atrial fibrillation population: the Complications of Atrial Fibrillation in the Bologna Area (CAFBO) study.

Background: Ischemic events (IEs) and intracranial hemorrhages (ICHs) are feared complications of atrial fibrillation (AF) and of antithrombotic treatment in patients with these conditions.
Methods: Patients with AF admitted to the EDs of the Bologna, Italy, area with acute IE or ICH were prospectively recorded over 6 months.
Results: A total of 178 patients (60 male patients; median age: 85 years) presented with acute IE. Antithrombotic therapy was as follows: (1) vitamin K antagonists (VKAs) in 31 patients (17.4%), with international normalized ratio (INR) at admission of < 2.0 in 16 patients, 2.0 to 3.0 in 13 patients, and > 3.0 in two patients; (2) aspirin (acetylsalicylic acid) (ASA) in 107 patients (60.1%); and (3) no treatment in 40 patients (22.5%), mainly because AF was not diagnosed. Twenty patients (eight male patients; median age: 82 years) presented with acute ICH: 13 (65%) received VKAs (INR, 2.0-3.0 in 11 patients and > 3.0 in two patients), while six (30%) received ASA. Most IEs (88%) and ICHs (95%) occurred in patients aged > 70 years. A modeling analysis of patients aged > 70 years was used to estimate annual incidence in subjects anticoagulated with VKAs in our Network of Anticoagulation Centers (NACs), or those expected to have AF but not included in NACs. The expected incidence of IE was 12.0%/y (95% CI, 10.7-13.3) in non-NACs and 0.57%/y (95% CI, 0.42-0.76) in NACs (absolute risk reduction [ARR], 11.4%/y; relative risk reduction [RRR], 95%; P < .0001). The incidence of ICH was 0.63%/y (95% CI, 0.34-1.04) and 0.30%/y (95% CI, 0.19-0.44), respectively (ARR, 0.33%/y; RRR, 52.4%/y; P = .04).
Conclusions: IEs occurred mainly in elderly patients who received ASA or no treatment. One-half of patients with IEs receiving anticoagulant treatment had subtherapeutic INRs. Therapeutic approaches to elderly subjects with AF require an effective anticoagulant treatment strategy.